Here's a photo of a few trannys laying in my barn.The one on top is a Saginaw 4 speed,identical to the 3 spd in appearance except for the 3rd shift lever.The bottom tranny is a Muncie 3spd,this particular unit is from a late 50's truck. Some Muncies have a provision for a rear mount as used for cars.
Some trucks used what's called a heavy duty 3 spd,I've never seen one, but I believe they are a Warner unit, maybe a T-85
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